Hello, I'm new here
So I have my Olimex USB(https://www.sparkfun.com/products/8702) programmer that is connected to an Atmega8-16pu via a 6 pin connector without an external oscillator, and with external power to the circuit from a wall-plugged ~120VAC to 5VDC USB converter.
it worked completely fine using AtmelStudio 6.2, i managed to program it and modify the circuit until(after a day or two of successful operation) I suddenly saw the message -
"Unable to enter programming mode.
Failed to enter programming mode. ispEnterProgMode: Error status received: Got 0x80, expected 0x00 (Command timed out)"

Steps I took to fix the problem were:
*I removed all the connections to the MCU except for the programmer's,
*I double checked the pins
*Replaced the chip with another atmega8-16pu
*reflashed the Programmer's firmware
*I went to AVR freaks, I was told to remove the programmer's driver from my PC, restart and replug+reinstall the driver,
so I did, it didn't work.

I am lost

What might be the cause of it? how can I check for the cause?
Thank you in advance!